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Monthly Archives: January 2017

2017 is not just another year, it’s the year of Hearing Loss Prevention.

Make the most of your hearing health in 2017

New hearing technologies and increased awareness of hearing loss points to 2017 as being the “Year of the Ear.” If you haven’t already made your New Year’s resolutions, consider what you can do to protect your hearing and be more hearing health conscious. We’ve compiled a list of a few things that you might want to consider for the new year.

Hearing Health & Loss Prevention

Hearing loss prevention is an action where you take special precautions to ensure your hearing is not being negatively affected. Sometimes the loss itself can be difficult to identify, which is why it’s so important to be on top of changes that may occur to your hearing.

Your hearing health has a direct effect on your overall health. Hearing loss has been linked to numerous medical issues, including viruses, bacteria, heart conditions or strokes, head injuries, tumors and certain medicines.

Heart health: Studies show that a healthy cardiovascular system – a person’s heart, arteries and veins – has a positive effect on hearing. Inadequate blood flow and trauma to the blood vessels of the inner ear can contribute to hearing loss.

Hypertension: There is a significant association between high blood pressure and untreated hearing loss. Hypertension can be an accelerating factor of hearing loss in older adults.

Smoking: Current smokers have a 70 percent higher risk of having hearing loss than non-smokers.

Diabetes: Hearing loss is twice as common in people with diabetes compared to those without. Adults whose blood glucose is higher than normal but not high enough for a diabetes diagnosis, have a 30 percent higher rate of hearing loss compared to those with normal blood sugar.

Ototoxicity: There are more than 200 medications (prescription and over-the-counter) on the market today that are known to be ototoxic or “poisonous to the ears.” Some known ototoxic drugs are: Aspirin, Quinine, Loop diuretics (or “water pills”), certain antibiotics, and some environmental chemicals.

Make sure you are making an annual hearing test part of your hearing health routine. Many hearing clinics provide free testing. If you haven’t already, schedule your next evaluation for the new year today.

Protect Your Ears

Noise-induced hearing loss (NIHL) is increasingly becoming a problem, especially for people aged 12 to 35. With the growing popularity of personal listening devices, taking steps to protect your hearing has never been more important. Take steps to ensure that you are listening at an appropriate volume, and use earplugs in heavily noise-polluted environments such as sports venues, hunting, shooting, concerts, or other events and activities that are loud. As little as 10 seconds at a loud stadium or concert can cause permanent hearing damage. Learn More about Hearing Protection.

Take Steps to Treat Hearing Loss

A shockingly large number of people that could benefit from using hearing device don’t use one. Hearing aid technology has improved significantly in recent years, and it’s worth exploring what kind of solutions there are that could make your life easier. You might be surprised by what a hearing aid device can do to improve your quality of life. If you’re suffering from hearing loss and haven’t considered treating it, now is the time!

Don’t Be Afraid to Ask for Help

Every person’s hearing is unique, almost like a fingerprint. When it comes to issues like hearing loss, tinnitus, hearing technology etc. don’t be afraid to ask a professional for advice. Your audiologist can help you make informed decisions about your hearing health and start on a path toward better living.

With the New Year here and moving with a vengeance, it is important to be proactive especially where your health is concerned. Whether it is your hearing, or a colleagues hearing, please educate and pass this message on.

Let’s prevent Hearing Loss, one ear at a time.

One in five Canadians aged 20 to 79 was found to have a hearing loss in at least one ear when tested audiometrically. Among those aged 70 to 79 the figure was 65%. Overall less than 4% reported themselves to have a hearing loss.

Almost one in five Canadians aged 20 to 79, an estimated 4.6 million adults, was found to have a hearing loss in at least one ear when tested audiometrically. Among those aged 70 to 79 the figure was 65%. Fewer than 4% of the adults reported having a hearing loss themselves. This is the result of a Canadian study published in Health Reports, which shows large disparities between self-reported and measured prevalence of hearing loss.

Mild hearing loss is rarely self-reported

12% of the Canadian adults were found to have a mild hearing loss. These people would be less likely to be aware of or self-report their hearing difficulty and would cope by using adaptive measures such as moving closer to the source of the sound or increasing the volume. For 7% of adults, hearing loss was moderate or severe.

In Canada, the prevalence of hearing loss has typically been estimated through self-reports. However, self-reports may result in underestimates, especially among older adults and among people with mild hearing loss or high-frequency hearing loss.

10.4 million with hearing loss by 2036

According to the study, the number affected is likely to rise substantially in coming decades and is projected to double from 5 million in 2011 to 10.4 million by 2036.

Despite the fact that the study results show a significant number of hearing impaired Canadians, the prevalence of hearing loss may still be underestimated. The study used both collected audiometric and self-reported data from the Canadian Health Measures Survey which only includes data of the population aged 20-79. People aged 80 or older is not included in the data and hearing loss is known to be more common with age.

Just How Important is Proper Fitting for Your Personal Hearing Protection Device?

Whether you wear a personal Hearing Protection Device (HPD) in your work environment or for recreational activities just how important is proper fitting for your personal hearing protection device?

With so many options on the market for styles of hearing protection ranging from a simple ear plug to very detailed styles of Custom Protect Ear’s moulded or 3D produced personally fitted HPD’s, how do you choose which is best for your hearing protection? Do you choose simply on the sophistication or level of the noise cancelling aspect or does proper fitting also factor in to your decision.

The number one indicator of how effective a HPD will be is if you actually wear it!!!

If your HPD is not comfortable will you be less likely to wear it or want to wear it? If you do wear it but because of improper fitting it is less effective than you assume it will be, you will not achieve the protection level you may need.

According to a publication in The National Institute for Occupational Safety and Health (NIOSH), they state that

In fact NIOSH was so concerned over the effects of poorly fitting HPD’s that they developed and licensed a system to create a fast and reliable fit-test system that measures the amount of sound reduction an individual worker receives from the HPD and identifies workers that are not sufficiently protected.

What are some concerns with improperly fitting HPD’s?

If your HPD is uncomfortable will you be more likely to remove it for periods of the time you need protection.

Will you be more likely to be distracted by the discomfort it is causing and be more aware of your discomfort than you are on your job or activity? Could you suffer from headache or earache induced discomfort from an improper fit?

If moisture is trapped in your ear with not enough air circulation could this lead to an increase in ear infections with possible infection induced damage?

If your HPD’s are designed to be able to hear communications or certain noises or sounds, would that communication level be reduced or hindered with improper fit? Would this encourage the user to possibly remove the HPD so that they can hear that communication leaving them open to noise induced hearing damage?

Have you or your Employer taken the steps to incorporate fit testing into your hearing protection plan? If not, start today! Ask about FitCheck Solo

With the properly style of hearing protection device based upon your particular needs and the proper fitting of that device you can dramatically increase your hearing protection, and isn’t that what you would expect from your HPD?

DRIL-COM – A new way for evaluating hearing protectors

When trying to determine whether a hearing protection device (HPD) can be effective for use in a given noisy environment, the conventional method has been to examine attenuation using SNR(SF84), its NRR(SF), or its derated NRR. Going to extremes, the individual mean octave-band attenuation values might be compared to the octave-band levels of the noise of concern to determine what the Assumed Protective Value (APV) might be with some allowance for the reported standard deviations of the attenuations.

All of these values will shed light on how effective the HPD should be in reducing potentially harmful noise to a safe level under the HPD. However, none of these values shed any light on how useable the HPD is in allowing the wearer to maintain environmental awareness. In construction, in manufacturing, and in the military, being aware of what’s happening in the surrounding areas can be as important to personal safety as the HPD is to the prevention of noise-induced hearing loss (NIHL).

Historically, when those who are supposed to use HPDs are asked why they don’t or won’t, the rank ordering of reasons is:

Interference with their ability to hear speech of other workers or team members;

Inability to hearing warning signals;

Inability to hear what is going on around them;

Inability hear the equipment that they are using; and

Comfort, or lack of it including heat buildup for earmuffs.

Those top five reasons can be lumped into one category:

Reduction of necessary auditory awareness.

For the military, auditory awareness is critical for troops in combat. Each soldier or marine leaving for a combat zone is issued, at present, the 4th generation of the so-call . It is a multi-flanged, premolded earplug with a passage through its center that passes through an acoustic filter that is supposed to have little effect for sound levels below 120 dB SPL and then increase in attenuation as the sound level increases.

The technical label for this technology is non-linear passive level-dependent. This technology has been around for decades and was first developed and tested by ISL in France. Ideally, an HPD such as the Combat Arms earplug would have no effect on auditory awareness for most signals.

Similarly, there are HPDs that are powered, either by their own battery or from a battery pack worn by the user that powers the HPD as well as other equipment. The technical term for theses HPDs is non-linear active level-dependent. The word “active” applies to the use of a powered electric circuit that passes all sound from the outside world into the ear of the wearer and then adjusts its gain or volume as the level of the outside sound increases until cutting off. Once cut off, the wearer experiences the full passive attenuation that the HPD provides. These types of devices are very popular among shooters and hunters in non-military applications. It is presently unclear about their deployment for military use.

DRIL -COM – The Research Case Study

Dr. John Casali at Virginia Tech University (VTU) has been a strong proponent of the importance of the auditory awareness effects of HPDs. There are reported incidences every year of workers who are hurt by equipment because their auditory awareness was impaired by the HPD they were wearing. These accidents include being run over by fork lifts, being run into by robotic parts delivery vehicles, and being hit by moving materials, such as delivered by crane at construction sites. All due to an HPD-induced inability to hear the necessary auditory cues that would have allowed them warning to get out of the way. For the soldier in combat who is using an HPD, the inability to clearly hear the approaching of what could be enemy personal, to hear the bolt noise from a rifle or the sliding in of an ammunition magazine, or even to hear the retort of a weapon fired at a distance can be life and mission endangering.

After years of work on auditory awareness issues for the larger employment universe, Dr. Casali focused on setting up a proof-of-concept project to show how to determine the effect of HPDs on auditory awareness. The method was given the name DRIL-COM, with each of the letters in the first word having meaning:

D – Detection.

The ability of the HPD user to even detect the presence of a sound either in quiet, in the presence of low-level background noise, or the presence of high-level background noise.

R/I –

Recognition/Identification. The ability to determine what made the sound. The reaction to a friendly sound should be different that the reaction to an unfriendly sound. Consider the swishing of reeds against each other as one fellow soldier returns from the latrine verses the sound of a magazine being slipped into an AK-47 by an unfriendly. Once a sound is detected, it must be recognized correctly and quickly.

L- Localization.

The last step of DRIL is localization, the ability to quickly determine the direction from which the sound came. In the case of a worker trying to avoid being run over, it’s ­important to know from where the sound of the approaching vehicle came. For the soldier, it’s important to know from where came the sound of the magazine being slipped into a weapon before break out of a fire fight.

COM – Communications.

Though not a letter, it is just as important. Each HPD has its own impact on communication, particularly in the presence of background noise. The COM portion of DRIL-COM evaluates that.

How was DRIL-COM administered?

In a large space to be as acoustically dead as possible so that all signals generated by the system could arrive at the listener without dealing with room reflections. Further, the technique was administered computer software and electronics. However, nothing was so specialized that it couldn’t be easily replicated by another laboratory; it is not ready for field deployment just yet.

The HPDs tested were:

3M 4th Generation Combat Arms™ earplug in the open setting, INVISIO X50™, Nacre-Honeywell Quiet Pro+™, Peltor Con Tac III™, Etymotic EB15LE™. Performance for all the HPDs was compared to ears open with no HPD.

What the results showed, in general, was that there was no HPD that was as effective in all the DRIL-COM categories as the open, unprotected ear. While each HPD provided some degree of protection from noise, none allowed the critical elements of auditory awareness to be as effectively managed as ears open with no HPD. Unfortunately, soldiers appear to have figured this out for themselves. Of those going into combat in Afghanistan who were issued the Combat Arms earplug, 30% have come back with NIHL (Noise Induced Hearing Loss) that they did not have upon deployment BECAUSE THEY DID NOT USE the earplugs as they needed to maintain auditory awareness.

Of interest was the final combined ranking of the tested HPDS in the DRIL-COM testing. Worse were the Combat Arms earplug, the Quiet Pro max and the Quiet Pro when set to unity gain. Max is when the gain of the HPD is set to full on, which is possible with active non-linear HPDs. Unity gain means that the sound level outside the HPD is the same as inside. These three HPDs (settings) were statistically significantly worse than all the other HPDs tested in all conditions. Following, and statistically different from ears open but not from each other, were Com Tac III unity, Com Tac III max, X50 unity, X50 max, EB15LE unity, and EB15LE max.

So, what’s the take away message from the DRIL-COM tests.

First is that there is a method that can be deployed to determine the impact of an HPD on auditory awareness. It is not a method that an end user can deploy easily, but it is one that a testing laboratory or manufacturer could set up and run and then assign a number for auditory awareness to their product. Further, manufacturers could work to make sure that their HPDs have as little impact on auditory awareness as possible.

“This is why only dB Blockers double-vent their protectors when connecting a radio to them”.

Clearly, for the worker who needs 25 dB of protection this may not be important or possible. But, since most workers need 15 dB or less of protection in most situations, and in some need none but work in fluctuating noise levels, auditory awareness may become more important in selecting an HPD than mere attenuation.

Second, at present, almost anything that is stuck in the ear or placed over it tends to interfere with auditory awareness. Prior to the late 1970s the pinna (outer ear) was thought to be a vestigial organ. It sits on the side of the head, it is immobile, and best for holding eyeglasses and decorating with earrings. But it proved to not be case. The pinna is a critical organ for auditory awareness.

It allows the listener to locate origins of sounds in space, it enhances high-frequency hearing, and the central auditory system has learned how to use it. No two pinnae are quite alike, however, and so it is difficult to develop a universal surrogate that can be incorporated into an HPD.

Case in point is the Combat Arms earplug.

In its open condition, it is simply a tube with a small filter in in that is not supposed to effect low-levels of incoming sound. At face value, it would seem to be the best solution. But the DRIL-COM testing showed it to be the composite worst. Its alternation of the pinna’s acoustics, even though the HPD was deeply inserted. On the other hand, the EB15LEE, which is an active earplug, seemed to be the least destructive in both its unity and max settings. It is a digital processing system that might be further taxed to calculate the harm it has caused ear acoustics simply by its insertion and then develop a new algorithm to make the EB15LE effectively acoustically invisible. That type of protector could take into account the natural acoustics of the pinna and further undo its deleterious effects until it was neutral in both of its setting, unity and max.

For a passive non-linear HPD to be effective in terms of auditory awareness, it would have to be deeply inserted so that is outer surface was inside the ear canal, much like and completely-in-the-ear canal (CIC) hearing aid, but then it would be difficult to use in both the open and closed settings as the Combat Arms earplug is. There is possibly a solution available, but it would need to be submitted to a DRIL-COM test protocol to prove it.

The Virginia Tech Auditory Systems Laboratory (ASL) research effort for the DoD Hearing Center of Excellence was aimed at the development of an efficient, in- laboratory implementable test battery for auditory situation awareness (ASA) that objectively quantified the ASA performance afforded by various Tactical Communications and Protection Systems (TCAPS) and augmented/advanced Hearing Protection Devices (HPDs) used by the U.S. military. Specifically, each of the fundamental ASA task elements of Detection, Recognition/Identification, Localization, and COMmunications, hereafter termed “DRILCOM” ASA elements, was measured in the psychophysical test battery that was the primary deliverable from the research. The individual ASA elements’ scores from the test battery were kept separate so that performance on each element of ASA could be ascertained, and via statistical analysis, the individual elements’ sets of scores were applied to determine the DRILCOM test battery’s effectiveness in measuring ASA afforded by each TCAPS or augmented HPD. The intent was that the test battery would ultimately be deployable in a military audiology clinical or other similar laboratory setting, and applicable to a wide variety of TCAPS and HPDs.